Author Contributions: Dr Sone had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: Kodama, Saito, Maki, Yamada, Sone.
Acquisition of data: Kodama, Yachi, Sugawara, Totsuka.
Analysis and interpretation of data: Kodama, Tanaka, Asumi, Shimano, Ohashi, Yamada, Sone.
Drafting of the manuscript: Kodama, Maki, Sone.
Critical revision of the manuscript for important intellectual content: Kodama, Saito, Tanaka, Yachi, Asumi, Sugawara, Totsuka, Shimano, Ohashi, Yamada, Sone.
Statistical analysis: Kodama, Saito, Tanaka, Ohashi, Sone.
Obtained funding: Sone.
Administrative, technical, or material support: Kodama, Saito, Tanaka, Maki, Yachi, Asumi, Sugawara, Totsuka, Shimano, Ohashi, Sone.
Study supervision: Yamada, Sone.
Financial Disclosures: None reported.
Funding/Support: Drs Kodama and Sone are recipients of a Grant-in-Aid for Scientific Research and Postdoctoral Research Fellowship, respectively, both from the Japan Society for the Promotion of Science (JSPS). This study was also supported by Ministry of Health, Labor and Welfare, Japan.
Role of the Sponsors: The research organizations providing funding support did not have any role in the design and conduct of the study, in the correction, management, analysis, and interpretation of the data, or in the preparation, review, or approval of the manuscript.